linux kernel : page frame management
Linux adopts the smaller 4KB page frame size as the standard memory allocation unit. this makes things simpler for two reasons :
1. The Page Fault exceptions issued by the paging circuitry are easily interpreted. either the page requested EXISTS but the process is NOT ALLOWED to address it, or the page does NOT EXISTS. in the second case, the memory allocator must find a free 4KB page frame and assign it to the process.
2. Although both 4KB and 4MB are multiples of ALL disk block sizes, transfers of data between main memory and disks are in most cases more EFFICIENT when the smaller size is used.
excerpted from Bovet, Cesati :Understanding the Linux kernel, 3rd ed., page 294-5.
linux kernel 讀書筆記
Wan Chin :
Roger Lee :
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